ROMMEL C. SULABO

Dept. of Animal Sciences & Industry

Kansas State University

Value of Non-Phosphorus Effects Value of Non-Phosphorus Effects of Exogenous Phytase in Swineof Exogenous Phytase in Swine

OutlineOutline

I. Introduction

II. Phytase and protein/AA utilization

III. Phytase and energy utilization

IV. Use of phytase matrix values

V. Discussion

VI. Evaluation and conclusions

Introduction

Wide acceptance of phytase use in pig and poultry diets: Increased environmental legislation Ban of animal origin P sources (e.g. EU) Lower feed enzyme inclusion costs relative to

inorganic P sources Increasing ingredient costs (corn, SBM, etc.) More commercial sources of phytases

Current ideas of phytase use: account for potential effects in improving protein/AA and energy utilization

Introduction

Phytic acid:Myo-inositol hexakisphosphatePoly-anionic molecule with a tremendous capacity to bind positively-charged nutrients (‘chelating capacity’)Probable basis of its anti-nutritive properties

H

O

P

O

OO

H

O

P

OH

OO

H

O

P

O

OO

H

O

P

O

OOH

O

P

O

OOH

OH

P

O

OO

O O

O

CH2OH

STARCH

+ Ca +

+ Ca +

O C PROTEIN

O

CH2

NH3

CH2

PROTEIN

STARCH

Thompson, 1988

Interactions of phytic acid with protein, minerals and starch

Binary nutrient-phytate complex

Ternary nutrient-mineral-phytate complex

Net Variable Cost (or Savings) with Phytase Supplementation

Net Cost Change equals summation of: Added Cost > Cost of phytase > Cost of added ingredients due to phytase

addition

Added Returns > Value of reduced ingredient needs due to

phytase > Value of reduced P excretion in pig manure

ItemItemNatuphos®

5000Ronozyme® P5000 (CT)

Phyzyme XP® 5000

Optiphos® 2000

Dose (U/kg) 500 750 500 250

Inclusion rate (g/ton) 100 150150 100 125

Nutrient matrixNutrient matrix

Total P (%) 1111 342?342? 1329 --

Available P (%) 1000 -- 1196 960

Ca (%) 1000 232?232? 931 672

DE (kcal/kg) 98958 -- 304398 --

ME (kcal/kg) -- -- -- 76000

Dig Protein (%) 2000 -- 2444 1600

Dig Lys (%) 80 -- 151 64

Dig Met (%) 25 -- 46 20

Dig Cys (%) 30 -- 102 --

Dig Thr (%) 50 -- 237 40

Dig Trp (%) 30 -- 62 24

Dig Leu (%) 120 -- 404 --

Nutrient matrix values of commercial phytases for pig diets

1. Protein/AA effects

Introduction

Rojas and Scott (1969) – first suggested the potential interaction between phytate and protein utilization in poultry

Possible interactions1: Presence of protein-phytate complexes in feedstuffs De novo formation of binary and ternary protein-

phytate complexes in the digestive tract Phytate inhibition of proteolytic enzymes (e.g. trypsin

activity?)

1Selle et al. (2000)

De novoDe novo formation formation of protein-phytate of protein-phytate

complexescomplexes

Pre-Pre-bound bound dietary dietary protein protein

less less readily readily

digesteddigested

Pigs: Stomach

Poultry: Crop, Proventriculus,

gizzard

Small intestine

ProteinProtein PhytatePhytate

Proposed mode of action of phytate and phytase

Reduced absorption of dietary AA and reduced

re-absorption of endogenous AA

Mucin loss

Refractory to pepsin digestion

Additional outputs of pepsin and HCl

Extra mucin secretion

Na+ as NaHCO3

Reduction of Na+-dependent

transport and Na+-pump activity

Compromised AA uptakes

Selle et al. (2000)

Pig studies: Phytase vs. protein/AA utilization

No. Study nPig

type1 Diet Phytase2

Dose (FTU/kg) Method3

Inert Marker

1 Mroz et al. (1994) 5 G C-Tapioca-SBMA. niger

(N) 800 PVTC Cr2O3

2Johnston et al.

(2004) 8 G C-SBMA. niger

(N) 800 SICV Cr2O3

3 Liao et al. (2005a)-1 6 N C-SBM A. niger

(N) 500 T Cr2O3

Liao et al. (2005a)-2 6 N Wheat-SBM A. niger

(N) 500 T Cr2O3

Liao et al. (2005a)-3 6 N Wheat-SBM-canola A. niger

(N) 500 T Cr2O3

Liao et al. (2005a)-4 6 N Barley-peas-canolaA. niger

(N) 500 T Cr2O3

4 Liao et al. (2005b)-1 8 G C-Rice bran-SBMA. niger

(N) 2000 T Cr2O3

Liao et al. (2005b)-2 8 G C-SBMA. niger

(N) 2000 T Cr2O3

5 Radcliffe et al. (2006) 10 G C-SBMA. niger

(N) 500 SICV Cr2O3

1Pig type: G = grower, N = nursery 2Phytase: A. niger (N) – Natuphos®

3Method: PVTC = Post-valve T-cannulation, SICV = Steered-ileocecal valve T-cannulation T = Simple T-cannulation

All studies used Latin square design with n number of pigs and periods

Ave. adaptation period of 7 days (4-5 d adaptation to exptl. diets, 2 and 1-2 d for ileal digesta and fecal collection, respectively)

Effect of exogenous phytase on AID of CP in complete diets fed to pigs

Inclusion: 500 to 2000 U/kg

CP digestibility: Response (%) to phytase supplementation

Ph

yta

se

re

sp

on

se

(%

of

co

ntr

ol)

Effect of exogenous phytase on AID of mean AA in complete diets fed to pigs

Inclusion: 500 to 2000 U/kg

Ph

yta

se

re

sp

on

se

(%

of

co

ntr

ol)

Mean AA digestibility: Response (%) to phytase supplementation

Effect of phytase supplementation on the AID (%) of CP and AA in corn- and wheat-SBM diets fed to

nursery pigs

   

Corn-SBM Wheat-SBM

 Control

 Phytase

Response(%)

 Control

 Phytase

Response(%)

CP 0.76 0.76 0.26 0.83 0.84 0.36

Arg 0.86 0.87 0.46 0.89 0.89 0.56

His 0.84 0.83 -0.48 0.86 0.86 -0.23

Ile 0.79 0.81 1.51 0.86 0.86 -0.23

Leu 0.78 0.76 -2.44 0.86 0.86 0.00

Lys 0.76 0.76 -0.40 0.85 0.85 0.12

Phe 0.82 0.83 1.22 0.87 0.87 -0.12

Thr 0.73 0.73 0.00 0.78 0.78 -0.90

Val 0.76 0.77 1.06 0.84 0.83 -0.36Liao et al. (2005)

n = 6 barrows; Phytase (Natuphos at 500 FTU/kg) No effect of phytase level (500 vs. 1000 U)

   

Wheat-SBM-Canola Barley-Peas-Canola

 Control

 Phytase

Response(%)

 Control

 Phytase

Response(%)

CP 0.72 0.75 3.89b 0.73 0.74 0.27

Arg 0.82 0.85 3.17a 0.85 0.85 -0.23

His 0.82 0.85 4.16a 0.84 0.82 -1.32

Ile 0.75 0.79 4.51b 0.77 0.77 0.13

Leu 0.78 0.81 3.98b 0.79 0.79 -0.13

Lys 0.77 0.80 4.42b 0.82 0.82 0.24

Phe 0.78 0.82 4.99a 0.80 0.80 -0.13

Thr 0.69 0.72 4.93a 0.68 0.68 0.59

Val 0.73 0.77 5.18a 0.74 0.74 0.00

Effect of phytase supplementation on the AID (%) of CP and AA in wheat-SBM-canola meal and

barley-peas-canola meal diets

Liao et al. (2005) ; aP<0.05, bP<0.07

n = 6 barrows; Phytase (Natuphos at 500 FTU/kg) No effect of phytase level (500 vs. 1000 U)

Effect of reduction of dietary Ca and P and/or phytase addition on AID (%) of AA in diets for finishing pigs

Diet No.

1 2 3 4

Ca, % 0.50 0.40 0.50 0.40

aP, % 0.19 0.09 0.19 0.09

Phytase, U/kg 0 0 500 500 SEM

Lys 77.2 80.8 79.9 80.2 1.1

Ileab 77.3 81.6 81.0 81.6 1.0

Leuab 80.0 83.6 83.2 83.8 0.9

Pheab 78.4 81.8 81.1 82.1 1.1

His 83.4 86.0 85.3 85.6 0.9

Arga 85.7 87.1 86.9 88.3 0.8

Valab 76.6 82.0 79.0 81.1 1.1

Thrab 70.5 75.9 74.4 75.0 1.3

Trp 77.4 80.4 79.8 80.3 1.2n = 8 barrows; Contrasts: aDiet 1 vs. 4 = P<.05, bCa/aP = P<.06 Johnston et al. (2004)

Effects of dietary phytase and CP on N balance in growing pigs

Diet No.

1 2 3 4 5

Ca, % 0.44 0.44 0.44 0.44 0.44

P, % 0.40 0.40 0.40 0.40 0.40

CP, % 12.0 11.1 10.2 10.2 10.2

Phytase, U/kg 0 0 0 250 500 SEM

N intake, g/da 39.9 37.2 35.7 35.7 36.1 1.9

Fecal N, g/d 5.5 5.7 5.0 5.4 4.9 0.7

Urinary N, g/d 1.6 2.6 2.3 1.6 2.2 1.7

N digested, g/da 34.4 31.6 30.7 30.3 31.2 1.9

N retained, g/da 32.4 28.9 28.4 28.7 29.1 2.8

N digested, % 86.3 84.8 85.9 84.9 86.6 1.7

N retained, % 81.2 77.6 79.5 80.2 80.4 5.3n = 10 barrows; aLinear effect of protein level, P<.003 Radcliffe et al. (2006)

Effects of dietary phytase and CP on AID (%) of CP and AA in growing pigs

Diet No.

1 2 3 4 5

Ca, % 0.44 0.44 0.44 0.44 0.44

P, % 0.40 0.40 0.40 0.40 0.40

CP, % 12.0 11.1 10.2 10.2 10.2

Phytase, U/kg 0 0 0 250 500 SEM

CPab 73.8 72.0 66.7 69.3 70.1 6.1

Hisa 83.9 82.3 80.4 80.7 81.7 3.6

Lysab 79.4 78.2 72.7 76.3 76.0 5.5

Argab 87.1 85.8 84 85.3 85.9 3.1

Meta 79.8 78.6 75.8 77.2 78.0 4.4

Thrab 72.3 70.3 66 68.2 70.0 6.7

n = 10 barrows; Radcliffe et al. (2006)

aLinear effect of protein level, P<.005, bLinear effect of phytase, P<.07

Discussion

Fewer published data on the effects of phytase addition on the ileal digestibility of AA in pigs vs. poultry

Effect of exogenous phytase on AID of CP/AA digestibility in pigs:

- Variable and small responses (mostly no effect)

- Earlier study1: significant effect of phytase supplementation in 10 AA in slaughtered pigs vs. 4 AA in cannulated pigs (effect of method?)

- Protein deposition studies – more appropriate method to determine effect of phytase on protein digestibility

- Lack of data – no growth performance study evaluating phytase vs. protein utilization in pigs

- No data evaluating effects of phytase on TID values in pigs1Kornegay et al. (1998)

Discussion

N balance study: No effect of phytase on N retention in pigs1

- Numerous broiler studies showed similar effects of phytase addition on N retention and protein efficiency ratio (PER)2

Effect of dietary ingredients: Inconsistent effect of phytase addition in weanling pigs, positive effect only in wheat-SBM-canola meal diet

- Largest theoretical response to phytase is expected when diet is high in phytate and low in intrinsic phytase activity

- Liao et al. (2005b): no difference in AID of AA between high vs. low phytate diet

- Phytate-P per se may not be a primary determinant; it may be the amount of AA complexed with phytate-P?

1Radcliffe et al. (2006)

2Ledoux and Firman (2001); Boling-Frankenbach et al. (2001)

Effect of exogenous phytase on flow and composition of endogenous AA losses

Cowieson and Ravindran (2007): Evaluated the effects of supplemental phytase and phytate on flow and composition of endogenous protein in the ileum of 28-d old broilers

Phytase effect – ameliorate effect of phytic acid in increasing ileal endogenous AA flow?

Previous work showed that phytate ↑ and microbial phytase ↓ excretion of sialic acid, an endogenous compound associated with gastrointestinal mucin1

May help explain the variability in AA responses to phytase and understand the mode of action in relation to AA

1Cowieson et al. (2004)

Casein diet EHC dieta

Casein 180 --

EHC -- 200

Dextrose 670 647

Vegetable oil 50 50

Cellulose 35 35

DCP 24 24

Na-bicarbonate 20 20

K2HPO4 12 12

Salt 4 4

Titanium oxide -- 3

MgO 2 2

Mineral premix 2.5 2.5

Vitamin premix 0.5 0.5

aPhytic acid (purified source) added at 0, 8.5, 11.5 or 14.5 g/kg ; Microbial phytase (Phyzyme XP) at 0 or 0.1 kg (500 FTU)

Experimental diets

Ileal endogenous flow of the sum of AA (mg/kg DMI) as affected by dietary phytate level and phytase

Na-phytate added to synthetic diet, corresponds to 2.4, 3.2 and 4.0 g/kg phytate-P; Phyzyme XP®

Cowieson and Ravindran, 2007

Ilea

l en

do

gen

ou

s A

A f

low

(m

g/k

g D

MI)

Amino acid (AA) composition of endogenous protein (g/100 g crude protein) in 28-d old broilers as

influenced by dietary levels of phytateA

min

o a

cid

co

mp

osi

tio

n (

g/1

00 g

CP

)

Increasing PA level influenced concentrations of Asp, Ser, Pro, Gly, Val, Leu, and His

Amino acid (AA) composition of endogenous protein (g/100 g crude protein) in 28-d old broilers as

influenced by microbial phytaseA

min

o a

cid

co

mp

osi

tio

n (

g/1

00 g

CP

)

Phytase inclusion:

= Asp, Thr, Ser, Gly, Cys

= Glu, Ala, Val, Phe

Discussion

Phytic acid (PA): ↑ flow of EAA and N with increasing phytate concentration

Microbial phytase: ↓ inimical effects of phytic acid on endogenous AA flow at all dietary phytic acid levels

Levels of PA and phytase: Both influenced the composition of endogenous protein

PA also selectively increased flow of some endogenous protein sources more than others (Asp, Ser, Thr, Tyr)

- Mucins – rich in Thr, Ser, Pro, Cys

Effects on AA digestibility should be evaluated based in TID (or RID) to account for changes in amount (composition) of endogenous AA losses

Effect of inert markers

Pig studies: all used chromic oxide as their inert marker for estimating nutrient flow

Broiler studies: Phytase response was inconsistent (summary of 13 AA digestibility studies)

Phytase responses were greater when either titanium oxide or acid-insoluble ash were used as dietary markers vs. chromic oxide

Selle et al. (2006): attributed the choice of markers as a potential source of variability in AA responses to phytase

Effect of digestibility marker on average increase in mean AA digestibility in broilers fed diets with and without phytase

Pe

rce

nt

2. Energy effects

Introduction

Theoretical basis1: - Phytate bind starch via H bonding

- Phytate has the capacity to inhibit α-amylase activity

- Phytate reduces glucose absorption in humans

Broiler studies: Positive effects on energy uitilization were reported1

Effects of phytase on energy digestibility in pigs are rarely studied

1Selle et al. (2006)

Pig studies: Phytase vs. energy utilization

No. Study nPig

type1 Diet Phytase2

Dose (FTU/kg) Method3

Inert Marker

1Johnston et al.

(2004) 8 G C-SBMA. niger

(N) 800 SICV Cr2O3

2 Liao et al. (2005a)-1 6 N C-SBM A. niger

(N) 500 T Cr2O3

Liao et al. (2005a)-2 6 N Wheat-SBM A. niger

(N) 500 T Cr2O3

Liao et al. (2005a)-3 6 N Wheat-SBM-canola A. niger

(N) 500 T Cr2O3

Liao et al. (2005a)-4 6 N Barley-peas-canolaA. niger

(N) 500 T Cr2O3

3 Liao et al. (2005b)-1 8 G C-Rice bran-SBMA. niger

(N) 2000 T Cr2O3

Liao et al. (2005b)-2 8 G C-SBMA. niger

(N) 2000 T Cr2O3

4 Nortey et al. (2007) 18 GWheat-wheat millrun-SBM E. coli (P) 500 T Cr2O3

1Pig type: G = grower, N = nursery 2Phytase: A. niger (N) – Natuphos®, E. coli (P) – Phyzyme XP®

3Method: SICV = Steered-ileocecal valve T-cannulation, T = Simple T-cannulation

All studies used Latin square design with n number of pigs and periods

Ave. adaptation period of 7 days (4-5 d adaptation to exptl. diets, 2 and 1-2 d for ileal digesta and fecal collection, respectively)

AID of energy (%) as affected by dietary phytase in pig dietsA

pp

are

nt

ilea

l dig

esti

bili

ty o

f G

E (

%) Ave: Control = 78.4, Phytase = 79.4 (+1.0%)

Effect of dietary phytase on apparent fecal digestibility in weaned piglets

n = 12 pigs/treatment; Kies et al. (2005)

Control diet

Phytase diet SEM P<

DM, % 82.6 84.6 0.45 0.05

N, % 80.2 82.0 0.52 0.09

Crude fat, % 81.9 83.1 0.26 0.05

Crude ash, % 45.0 54.8 1.40 0.02

Energy, % 84.7 86.0 0.41 0.10

Effect of dietary phytase on energy intake, energy loss, and heat production in weaned piglets

n = 12 pigs/treatment; Kies et al. (2005)

Control diet

Phytase diet SEM P<

GE intake 1162 1162 2.8 0.84

DE intake 983 1000 6.8 0.19

ME intake 958 961 3.1 0.65

Urinary energy 19 32 5 0.17

Methane production 5.5 6.7 0.16 0.02

Total HP (Htot) 638 640 3.2 0.66

Activity related HP (Hact) 123 122 1.5 0.55

Activity corrected HP (Hrest) 515 519 3.8 0.55

Total energy retention (RE) 213 249 24 0.37

Energy retention as protein (REp) 148 163 7 0.21

Energy retention as fat (REf) 65 86 17 0.46

ME for maintenance (MEm) 459 469 5 0.25

Effect of phytase level and ME intake on protein, fat, and ash accretion of growing pigs

ItemItem

2.9 x M 3.2 x M

SEM0 500 0 500

Protein deposition, g/d 92.5 101.4 110.3 112 8.9

Fat deposition, g/da 55.7 65.5 84.0 83.1 10.4

Ash deposition, g/d 14.6 11.6 17.0 14.6 3.1

Heat production, Mcala 3.14 3.21 3.41 3.39 0.07

Nem, Mcal/kg 1.45 1.50 1.55 1.53 0.04

Nep, Mcal/kg 0.75 0.83 0.88 0.90 0.07

RE, Mcala 39.8 46.0 54.8 53.9 5.0

n = 6 pigs/treatment; aEnergy, P<.05 Shelton et al. (2003)

Effect of diet on growth performance and ultrasound measurements of growing pigs

n = 128 pigs blocked by weight and ancestry (RCBD), 8 reps/trt and 4 pigs per replication Diets: (1) C-SBM control and (2) C-SBM with 0.10% lower P and Ca + 500 U/kg phytase Shelton et al. (2003)

Item Control Phytase SEM

ADG, kg 0.85 0.84 0.02

ADFI, kg 1.92 1.85 0.04

G/F 0.44 0.45 0.01

Ultrasound measurements

Initial LMA, cm2 10.48 10.44 0.12

Final LMA, cm2 17.28 17.58 0.25

Initial 10th-rib fat, cm 0.91 0.87 0.03

Final 10th-rib fat, cm 1.40 1.43 0.04

LMA difference, cm2 6.83 7.11 0.21

10th-rib fat difference, cm 0.49 0.56 0.05

Discussion

Effect of phytase on energy digestibility: 11/14 (80%) comparisons showed no response to phytase addition in pigs

No effect of phytase addition on total energy retention (RE) in weaned pigs and growing pigs (for pigs fed 3.2 x M)

Phytase addition increased fat deposition, HP, and RE numerically in growing pigs fed 2.9 x M

No effect of phytase addition on growth performance and ultrasound measurements in finishing pigs

3. Use of phytase matrix values

Using nutrient matrix values

Maintain performance at lower feed cost

Optimize least cost formulation using the nutrient equivalencies for P, Ca, AA and energy from X amount of phytase

“Down-spec” or enter phytase a a feed ingredient with nutrient values

Reduce feed cost and improve performance

Incorporate X amount of phytase to replace P and Ca from mineral sources; plus utilize extra nutients released to realize benefit in performance

Nutrient matrix values used in the study

NutrientMatrix value

Amount provided in the diet

Available P, % 188 0.094

Ca, % 188 0.094

CP, % 427 0.214

Lys, % 29 0.015

Met, % 5 0.003

Cys, % 10 0.005

SAA, % 15 0.008

Trp, % 6 0.003

NutrientMatrix value

Amount provided in the diet

Thr, % 24 0.012

Val, % 26 0.013

Ile, % 22 0.011

Leu, % 33 0.017

Arg, % 16 0.008

Phe, % 21 0.011

His, % 11 0.006

ME, kcal/kg 61937 30.969

Natuphos 1200 added at 0.05% of the diet, 500 FTU/kg

Growth performance of broilers using nutrient matrix for AA, Ca, and aP

Data are means of 7 reps of 6 broilers/rep (14 d trial); abP<.03

Diet 2 deficient in AA = 0.82% TID Lys (vs. 1.12%), rest of AA met or exceeded ratio to Lys Diet 3 = Diet 2 + phytase with nutrient matrix values for AA, Ca, and aP Diet 4 = Diet 3 with no phytase but with supplemental Ca and P

Shelton et al. (2004)

Treatment ADG ADFI G/F

1. C-SBM control diet 41.3a 51.4a 0.80a

2. C-SBM deficient in AA 33.9b 49.0a 0.69b

3. C-SBM diet deficient in AA but with 600 FTU/kg 33.2b 49.0a 0.68b

4. Diet 3 without phytase but adequate in Ca and aP 33.1b 48.6b 0.68b

SEM 0.7 0.8 0.01

Treatment ADG ADFI G/F

1. C-SBM diet (Control) 41.3a 51.4 0.80a

2. C-SBM diet low in ME 38.1b 51.9 0.74b

3. C-SBM diet low in ME but with 600 FTU/kg 39.3b 52.6 0.75b

4. Diet 3 without phytase but adequate in Ca and aP 38.8b 52.7 0.74b

SEM 0.6 0.9 0.01

Growth performance of broilers using nutrient matrix for ME, Ca, and aP

Data are means of 7 reps of 6 broilers/rep (14 d trial); abP<.04

Diet 2 low in ME = 2937 kcal ME/kg (vs. 3200), Diet 3 = Diet 2 + phytase with nutrient matrix values for ME, Ca, and aP Diet 4 = Diet 3 with no phytase but with supplemental Ca and P

Shelton et al. (2004)

Effect of dietary phytase on growth performance of 42-d old broilers

Item

1 2 3

SEMControl MEME

and AA

Final weight, g 2220 2201 2189 13.2

ADG, g 51.7 51.3 51.0 0.3

Feed intake, g 94.1 92.8 92.0 1

Gain:feed, g:kg 549 550 552 5

Tibia ash, % 57.27 58.02 57.12 0.56N = 1575; Data are means of 10 reps of 105 broilers/rep Starter (0-15 d), Grower (16-35 d), Finisher (36-42 d)

Diet 1 = C-SBM control diet Diet 2 = Diet 1 + 600 FTU/kg phytase with nutrient matrix values for ME, Ca, and aP Diet 3 = Diet 1 + 600 FTU/kg phytase with nutrient matrix values for ME, AA, Ca, and aP Shelton et al. (2004)

1 2 3

Item Control MEME

and AA SEM

LW, kg 2.2 2.15 2.17 0.03

Eviscerated weight, kg 1.58 1.53 1.55 0.02

Chill weight, kg 1.62 1.57 1.58 0.02

Carcass yield, % 72.1 71.8 71.3 0.3Moisture gain due to chill, % 2.54 2.35 2.32 0.27

24-h moisture loss, % 1.1 1.07 1.05 0.08

Breast weight PLW, % 13.3 12.7 13.1 0.14

Effect of dietary phytase on carcass traits of 42-d old broilers

N = 1575; Data are means of 10 reps of 105 broilers/rep Shelton et al. (2004)

Discussion

Reducing AA or ME concentration in broiler diets resulted in decreased performance; phytase addition did not affect growth of broilers fed diets deficient in AA or ME

Using nutrient matrix values for phytase in formulating C-SBM diets for broilers resulted in similar growth performance and carcass traits

Authors: “matrix values are accurate and can be used in formulating diets for commercial broilers”

Basis of Natuphos® AA matrix values

Conclusions

Consistent response in improving P utilization by microbial phytase supplementation

Current body of evidence: Inconsistent and mostly lacking in any microbial phytase-induced improvement in protein/AA and energy utilization

Conflicting base of information

Implications

Cost effectiveness of phytase addition can be improved if phytase can consistently protein/AA and energy utilization

Lack of response in pigs - caution needed in using over simplistic guidelines (“AA and energy matrix values”)

Several factors merit further research

Questions?